Secret Test at Air Force Base Aims to Break Land Speed Record

Next week, engineers at Holloman Air Force Base in New Mexico will try to break a land speed record, blasting a rail-mounted rocket sled at Mach 8.9 during a test of a classified Navy system. The test is scheduled to occur Jan. 30, officials there tell PM.

The test is part of a secret project for the Navy, which is asking Holloman's test team to propel a secret payload, designed at Sandia National Laboratories, at 1.88 miles per second.

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In 2003, the same sled track (pictured above) was used to bust the standing land speed world record for a vehicle on rails. During that test, which sent payloads at Mach 8.47 (6453 mph), 13 rocket motors drove the sled in stages. As the first stage burned out, its sled detached and slowed while the next ignited. The test was performed to validate upgrades to the track, the world's longest, fastest test facility.

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The 10-mile Holloman High Speed Test Track is seen as a bridge between laboratory experiments and expensive, possibly dangerous test flights. It's used to test ejection seats, missile defense components, the impact strength of bunker-busting bombs and the release of sub-munitions at high speeds. Operated primarily for Air Force Materiel Command, the facility is also available to other government agencies and defense contractors. The Navy is one of the first agencies to bring its hardware out for testing on the upgraded track, Holloman officials say.

So what could they be testing? Not many things go faster than Mach 8--munitions from electromagnetic rail guns go that fast. Hypersonic missiles with scramjets can also reach those speeds--the airflow in a scramjet engine remains supersonic throughout the combustion process and does not require choking mechanisms to slow it down for mixing fuel and air. Sandia has worked with both electromagnetic propulsion and scramjet technology before, so either would make sense. The Navy has also tested antiship missile defense systems at Holloman--the interceptors that shoot down warheads go pretty fast, too.

"The Navy may release more details after the test," says Staff Sgt. Dave Wagstaff, a public affairs official at Holloman. "Then again, they may not."

Stay tuned: The sled-track folks promised to let us know the speed-related results of the test, if nothing else.